Andrew Lamb created ARROW-11862:
-----------------------------------
Summary: [Rust] String and BinaryArray created from iterators that
don't accurately report size can lead to undefined behavior
Key: ARROW-11862
URL: https://issues.apache.org/jira/browse/ARROW-11862
Project: Apache Arrow
Issue Type: Bug
Reporter: Andrew Lamb
As [~jorgecarleitao] says on
https://github.com/apache/arrow/pull/9588#discussion_r584290701
The (Rust) Iterator spec recommends, but does not require, that the iterator
reports a correct length. Consumer that lead to undefined behavior from an
incorrect size_hint are the causers of said undefined behavior.
The only case where consumers can trust the iterators' length is when the
interator implement unsafe trait TrustedLen. Unfortunately, TrustedLen is still
in unstable. For that reason, we have been exposing unsafe
Buffer::from_trusted_len_iter and the like for those cases.
So the code should be updated to handle the case where the reported `size_hint`
turns out to be incorrect
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
